This book examines educational improvement in Great Britain in recent years. It addresses three concerns: (1) develop better estimates of the extent to which schools have changed in their effectiveness over time; (2) understand the factors and strategies associated with changes in performance across schools; and (3) explore the school-improvement process so as to learn more about the difficulties and challenges schools face. To meet these concerns, a series of case studies were used to look at changes over a 5-year period in a wide range of schools that faced different challenges. Some of the schools served disadvantaged communities, whereas others occupied more affluent suburbs. The volume is divided into three parts. Part 1 focuses on frameworks and assumptions and the need to improve debate and provide a context for judging school improvement. Part 2 presents case studies of eight schools in the process of change. These case studies highlight the difficulties encountered as schools tried to discard traditional assumptions, how schools can improve without sensational tactics, the difference that effective leadership can make, and the factors that can motivate teachers to embrace change. The last part describes patterns of change, starting points for change, and ways to build for improvement. (Contains name and subject indexes and approximately 140 references.) (RJM)